Otters live on the coast as well as along inland
water courses. In coastal environments they forage
in intertidal and shallow rocky areas, feeding on
fish and crustaceans, and therefore come into contact
with certain types of fishing gear. They are known
to be attracted to eels, fish, and crustaceans which
are used as bait or caught in fyke nets and creels.
There is documented evidence of otter mortality
in fyke nets, creels (for lobsters, crabs and prawns),
fish farm nets and wade nets19,48,49
as well as through entanglement in lost fishing
net50. A survey of drowned otters in
lobster creels off the Uists revealed that the majority
drowned while foraging in depths of 2-5 m and that
mortality increased with the incorporation of a
parlour in the creels used in the area46.
Crab creels did not appear to pose such a threat
as the gear was usually set on sandy seabed in deeper
water, further offshore, and therefore outside the
favoured foraging area of otters47.

The majority of documented deaths of otters in
these types of fishing gear are of adult females46,48.
The areas of capture correspond to sites where the
fisheries operate near otter populations but data
suggest that eel fyke nets can also attract and
kill otters living at very low densities51.
A marked concentration of drownings in autumn and
winter has been recorded and may be partly explained
by the seasonality of fish and the fact that this
is when their main food may not be as easily available,
leading them to investigate prey in nets and pots51.
Various types of otter guards have been tested and
some form of guard is now mandatory for eel fyke
nets. No suggestions have been put forward on how
to reduce the threat from crustacean traps nor is
there a clear indication of whether mortality from
this cause is a conservation problem.

Summary of the potential effects of fishing on
otters

Fishery

Methods

Potential effects

Eels

Fyke nets

·
Inquisitive and foraging otters accidentally
caught in these nets has led to mandatory
use of otter guards.

Crustaceans

Pots and creels

·
Inquisitive and foraging otters accidentally
caught in these traps. Occurrence of accidental
capture may be linked to season and availability
of food.